Invisible inks have been known for quite some time. In the past, invisible ink has typically been used to write secret messages and/or codes, and configured to become visible upon treatment with heat and/or chemicals. Invisible inks are often still used as novelty items, children's toys, and for encoded data, where the invisible ink can be developed to become visible by employing appropriate chemistry.
People often use highlighting or underlining markers to write memory-jogging messages, highlights, and/or underlines correlated with written text. Existing highlighting practices often use markers that contain visible colorants, which can be fluorescent to draw attention to specific segments of important text. However, the color imparted by these highlighting markers can have an inherent messiness if not used with precision and care because of the difficulty of sketching freehand straight lines or the like. Also, messages, highlights, and/or underlines written with these markers typically cannot be reversed if needed or desired. Further, both the chemical and physical components of many existing highlighting markers can damage printed text and/or paper.
Recently, these problems have become exacerbated because of the use of personal computers and ink-jet printers for printing text. People often download information or input information into their personal computers for the purpose of printing readable text onto paper, where the paper containing the text is portable, highlightable, and can be easier to read. Ink-jet printing has become a popular way of recording text because of the low printer noise, the capability of high-speed recording, and multi-color recording at a relatively low price to consumers. Unfortunately, when an individual wants to highlight an inkjet printed passage of text using conventional highlighting markers, the highlighting can be irreversible, messy, and can smear the printed text. Thus, there is a need for providing an ink-jet system and method of use that would allow for an individual to print a passage of text and highlight the text, where the highlighting can be precise, reversible, and/or does not damage the printed text.